Three main components in Docker development

These are the small compilation of my learning for beginners who are new in DevOps, who want to learn about tools and techniques related to Containers, Docker, K8E, etc.

Let’s discuss these with the help of an illustration given below.

Building docker images

• Docker file: A docker file serves as the blueprint for an image. It is a simple text file that contains all the commands a user would call on the command line to create the image.
• Docker Image: As shown in the figure we build our docker image using that docker file we have created earlier. This image is an immutable file(they cannot be changed or read-only file) that contains the source code, libraries, and dependencies that are necessary for an application to run.
• Container: After our image is ready then we run this image and we have a running container.

What is the difference between a container image and a container?

It can be related to object-oriented programming, a container image is like a class, and a container is an instantiated object of that class.

Credits: Coursera course — Introduction to containers, docker,Kubernetes, open-shift.